CN101877899B

CN101877899B - Method and device for switching management

Info

Publication number: CN101877899B
Application number: CN201010190990.1A
Authority: CN
Inventors: 黄宏
Original assignee: ZTE Corp
Current assignee: Fengxian County Science And Technology Development Service Station
Priority date: 2010-06-02
Filing date: 2010-06-02
Publication date: 2014-08-13
Anticipated expiration: 2030-06-02
Also published as: CN101877899A; WO2011150622A1

Abstract

The invention provides a method and device for switching management, relating to the field of mobile communication, solving the problem of redundant process of directed retry process signaling. The method comprises the following steps: acquiring the directed retry signaling of a mobile terminal (MS) from the original cell to the target cell, wherein the directed retry information comprises information for managing the original cell and the target cell by the same base station controller (BSC); and directly switching the BSC for managing the original cell. The technical solution in the invention can be used for the field of signaling management.

Description

Switching management method and device

Technical Field

The present invention relates to the field of mobile communications, and in particular, to a handover management method and apparatus.

Background

The 3GPP organization in the prior art introduced an a interface (AoIP) for IP bearers. For the original A port signaling flow, a flow of directional retry is provided, wherein when the current cell has no available resources, the directional retry flow can automatically transfer the mobile phone to the cell which has spare resources around and meets the call quality, thereby improving the call completing rate and the service capability of the network. The general process of directed retry is as follows: when a Base Station Controller (BSC) receives an assignment request of a Mobile Switching center Server (MSC Server), it first tries to find available resources in a current cell, if not, it determines surrounding cells that can meet the call quality according to a measurement report of a Mobile phone, tries to allocate resources from the cells, and once the resource allocation and establishment are successful, it completes a directional retry.

In the handover standard protocol 23.009 of 3GPP, the handover occurring at call assignment is called directed retry, and its specific steps are shown in fig. 1:

s101, MSC SERVER sends an assignment request in the call establishment process;

s102, BSC sends MSC SERVER assignment failure response message, wherein the failure reason value in the message is directional retry;

s103, the BSC sends a switching requirement message;

s104, MSC SERVER sends a switching request;

s105, the BSC returns a switching request response message to MSC SERVER;

s106, MSC SERVER sending a switching command;

s107, the BSC sends a wireless switching command to the mobile phone;

s108, the mobile phone sends a wireless detection switching message to the BSC;

s109, the BSC sends a switching detection message to MSC SERVER;

s110, the mobile phone sends a switching completion message to the BSC;

s111, the BSC sends a switching completion message to MSC SERVER;

and S112, continuing the call establishment process.

In the process of realizing the above, the inventor finds that the following problems exist in the prior art:

as can be seen from the process shown in fig. 1, the directional retry procedure specified in the 3GPP standard protocol is a conventional handover procedure across BSCs, and requires information interaction with the BSC where the source cell is located and the BSC where the target cell is located, so that the signaling procedure is tedious and relatively complex. If the directional retry frequently occurs in the system, the signaling overhead and the switching delay are increased due to the existence of a tedious switching process, which will inevitably cause adverse effects on the network stability.

Disclosure of Invention

The invention provides a switching management method and a switching management device, which solve the problem of redundant signaling flow of a directional retry flow in the prior art.

In order to solve the technical problems, the invention provides the following technical scheme:

a handover management method, comprising:

acquiring directional retry information of a Mobile Station (MS) needing to be switched from a source cell to a target cell, wherein the directional retry information comprises information that the source cell and the target cell are managed by the same Base Station Controller (BSC);

and directly making a switching response to the BSC managing the source cell.

Further, the acquiring directional retry information that the MS needs to be handed over from the source cell to the target cell includes:

sending an assignment request to the BSC;

receiving a request from the BSC for the MS to handover from the source cell to the target cell, the request including information that a handover reason is directed retry;

determining directly from the request including a cause of handover that the MS needs to handover from the source cell to the target cell under a directed retry condition.

Further, the request including the cause of the handover is sent by the BSC after determining that the target cell is locally managed.

Further, the information that the source cell and the target cell are managed by the same Base Station Controller (BSC) is obtained by the following method:

and if the message format of the request of the MS for switching from the source cell to the target cell is the same as that of the external switching request, determining that the source cell and the target cell are managed by the same BSC.

Further, said responding directly to the Base Station Controller (BSC) managing the source cell for the handover comprises:

judging whether the local can support the switching requested by the BSC;

when the BSC can support the switch requested by the BSC locally, the BSC is informed to change the codec used by the call with the directional retry from full rate to half rate.

judging whether the local can support the switching requested by the BSC;

and when the local can not support the handover requested by the BSC, controlling the BSC to retransmit the request of the MS for switching from the source cell to the target cell.

Further, the controlling the BSC to retransmit the request for the MS to handover from the source cell to the target cell includes:

triggering the BSC to resend the request for the MS to switch from the source cell to the target cell by sending an assignment request to the BSC; or,

the BSC stops sending the MS's request again for handover from the source cell to the target cell by releasing the call where the directed retry occurred.

A handover management apparatus comprising:

an obtaining module, configured to obtain, in a call setup process, information that a Mobile Station (MS) needs to be handed over from a source cell to a target cell under a directional retry condition, where the directional retry information includes information that the source cell and the target cell are managed by a same Base Station Controller (BSC);

and the management module is used for directly making a switching response to the BSC for managing the source cell.

Further, the obtaining module includes:

a sending unit, configured to send an assignment request to the BSC;

a first receiving unit, connected to the sending unit, configured to receive, from the BSC, a request for handover of the MS from the source cell to the target cell, where the request includes information that a handover reason is directional retry;

a first determining unit, connected to the first receiving unit, for directly determining from the request including the reason for handover that the MS needs to be handed over from the source cell to the target cell under a directed retry condition.

Further, the request including the reason for handover received by the first receiving unit is sent by the BSC after determining that the target cell is locally managed.

Further, the obtaining module is configured to determine that the source cell and the target cell are managed by the same BSC according to that a message format of a request for handover of the MS from the source cell to the target cell is the same as a message format of an external handover request.

Further, the management module includes:

a first judging unit, configured to judge whether the local area can support the handover requested by the BSC;

and a notifying unit, configured to notify the BSC that the codec used for the call with the directional retry is changed from full rate to half rate when the BSC can locally support the handover requested by the BSC.

Further, the management module includes:

a second judging unit, configured to judge whether the local area can support the handover requested by the BSC;

and the control unit is used for controlling the BSC to resend the request of the MS for switching from the source cell to the target cell when the local can not support the switching requested by the BSC.

Further, the control unit is configured to:

Compared with the prior art, the technical scheme provided by the invention has the advantages that when the directional retry is initiated in the same BSC, the interaction with the BSC where the target cell is located is reduced by acquiring the information managed by the same BSC of the source cell and the target cell, so that the signaling interaction is reduced, and the switching speed is improved.

In general, timing retry is applied to a situation where an access cell is congested during call setup, and a call can be transferred to other cells that are relatively idle through directional retry. After the invention is adopted, because of the simplification of the processing and the reduction of the switching time delay, the directional retry can be applied to the scene of the cell congestion and can also be used for the optimization of the wireless resources. Through directional retry, the wireless resources can be reasonably allocated in the call establishment phase, and the throughput capacity of the system is improved. Furthermore, the message (external switching message) in the existing protocol is adopted to send the content that the source cell and the target cell belong to the same BSC, the realization is simple, and the problem of updating the network element equipment due to the modification of the message content can not occur.

Drawings

FIG. 1 is a schematic flow chart of a method for directional reproduction in the prior art;

fig. 2 is a schematic flowchart of an embodiment of a handover management method according to the present invention;

fig. 3 is a schematic structural diagram of an application example of the handover management method provided by the present invention;

FIG. 4 is a schematic structural diagram of an embodiment of a handover management apparatus according to the present invention;

FIG. 5 is a schematic structural diagram of an acquisition module 401 in the embodiment of the apparatus shown in FIG. 4;

FIG. 6 is a block diagram of an embodiment of the management module 402 of the apparatus shown in FIG. 4;

fig. 7 is another structural diagram of the management module 402 in the embodiment of the apparatus shown in fig. 4.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

Fig. 2 is a flowchart illustrating a handover management method according to an embodiment of the present invention. The embodiment of the method shown in fig. 3 comprises:

step 201, obtaining the directional retry information that the mobile terminal (MS) needs to switch from a source cell to a target cell, where the directional retry information includes the information that the source cell and the target cell are managed by the same Base Station Controller (BSC);

step 202, directly making a handover response to the BSC managing the source cell.

Compared with the prior art, the method provided by the embodiment of the invention has the advantages that when the BSC is subjected to directional retry, the interaction with the BSC where the target cell is located is reduced by acquiring the information managed by the same BSC of the source cell and the target cell, so that the signaling interaction is reduced, and the switching speed is improved.

The method provided by the invention is further described as follows:

fig. 3 is a schematic structural diagram of an application example of the handover management method provided by the present invention. The application example of the method shown in FIG. 3 includes:

s301, in the call setup process, MSC SERVER initiates an assignment request to the BSC, requesting to allocate channels and resources of port a.

S302, when the BSC detects that the MS needs to be switched from a source cell to a target cell, whether the target cell is managed by local is judged; if so, step S403 is performed.

In this step, the BSC detects that the MS needs to be handed over from the source cell to the target cell, and first determines whether the target cell is locally managed, since the BSC records all locally manageable cells, if the target cell belongs to a locally recorded manageable cell, indicating that the target cell is locally managed, it determines that the MS needs to initiate a directional retry in the BSC, that is, the source cell and the target cell are locally managed; the reason for the same BSC initiating the directed retry procedure may be congestion in the calling cell or optimization of cell radio resources. The triggering condition for optimizing the cell radio resource is newly added in the application example of the invention, wherein the triggering condition for optimizing the cell radio resource can be specifically the radio resource load is high, and the judging modes of the radio resource load state in the prior art are all suitable for the invention.

S303, the BSC sends MSC SERVER a request that the MS needs to handover from the source cell to the target cell under the directional retry condition, including information that the source cell and the target cell are managed by the same BSC.

In this step, the BSC detects that the MS needs to be switched from the source cell to the target cell, firstly judges whether the target cell is locally managed, and if so, determines that the MS needs to initiate directional retry in the BSC, namely the source cell and the target cell are locally managed; the reason for the same BSC initiating the directed retry procedure may be congestion in the calling cell or optimization of cell radio resources. The triggering condition for optimizing the cell radio resource is newly added in the application example of the invention, wherein the triggering condition for optimizing the cell radio resource can be specifically the radio resource load is high, and the judging modes of the radio resource load state in the prior art are all suitable for the invention.

Wherein the switching information may be sent in the following manner:

the first method is as follows: sending MSC SERVER an assignment failure response message including information that the failure cause is a directed retry, and sending MSC SERVER a request including a handover of the MS from the source cell to the target cell;

the second method comprises the following steps: and directly sending a request for the MS to switch from the source cell to the target cell, wherein the request comprises the information that the switching reason is directional retry.

Comparing the first and second modes, it can be seen that both the first mode and the second mode can achieve the purpose of notifying MSC SERVER that there is a local MS that needs to be handed over due to a reason of a directional retry, where the BSC in the first mode is sent through two messages, which are an assignment failure response message and a handover request message, and the BSC in the second mode only uses the handover request message, and sends the failure reason carried in the assignment failure response message in the first mode through the handover request message, which can be carried in an unused field, such as an extension field or a reserved field, in the handover request message, so that the assignment failure response message can be obtained in the second mode, and the exchange flow of information is reduced.

In both of the above-described manners, information managed by the same BSC for the source cell and the target cell may be transmitted through an unused field. For example, a field is selected, and when the value of the field is configured to be 0, it indicates that the source cell and the target cell are managed by the same BSC; when 1, it means that the source cell and the target cell are not managed by the same BSC. After the MSC receives the request, it can determine whether the source cell and the target cell are managed by the same BSC according to the value in the field.

Furthermore, in order to avoid the problem of upgrading network element equipment due to modification of the existing message, the message format of the message requesting for switching in the step is the same as the format of an external switching request applied to switching when the call enters a stable state in the existing protocol, which is not the format of the switching request in the traditional cross-BSC switching process, and the external switching request is applied to the call establishment process, so that the BSC can determine that the source cell and the target cell of the switching are managed by the same BSC according to the external request message in the call establishment process, and the method is simple and convenient; meanwhile, the message format specified in the existing protocol is adopted for sending, the realization is simple, and the compatibility of the messages between the systems is ensured.

S304, MSC SERVER determines that the source cell and the target cell are managed by the same BSC from the request for switching sent by the BSC, and then directly makes switching response to the BSC;

in this step, MSC SERVER determines whether the message requesting handover is an external handover request, and if so, it is determined that the message is managed by the same BSC.

Where the format of the external handover request is different from that of the conventional handover request, that is, the external handover request and the conventional handover request are two different message types, MSC SERVER may determine whether the message is an external handover request message according to the message type identifier in the received message.

If the message requesting handover is not an external handover request but a conventional handover request, MSC SERVER is processed according to a conventional handover procedure.

Through the judgment of the step, if the handover is managed by the same BSC and is not a cross-BSC handover mode, MSC SERVER does not need to follow the negotiation process (S104 and S105 shown in fig. 1) of the handover with the BSC where the target cell is located in the cross-BSC handover process in the prior art, thereby reducing the information interaction process.

In this step, it is determined whether the local area can support the handover requested by the BSC, and if so, the BSC is notified to allow the MS to perform handover; otherwise, the BSC is informed to refuse the MS to be switched. The reason for not supporting this handover may be a bearer establishment failure or radio selection to a suitable codec.

Optionally, when the MS is allowed to be switched, the BSC is further notified to change the codec used by the call of the MS from full rate to half rate, and compared with the prior art in which the codec rate is modified only when the call is in a stable state, the existing transmission mechanism is used to modify the codec rate in advance, thereby overcoming the problem that a large number of calls using the full rate codec exist in a cell with good wireless signals due to a long call setup time, improving the efficiency of using wireless resources, and achieving the purpose of optimizing cell resources.

Optionally, when the MS is rejected to be handed over, the BSC is controlled to retransmit the request for handing over the MS from the source cell to the target cell, so as to prevent the problem that the BSC frequently retransmits the message for requesting handover to the local after the handover fails, which causes a heavy local burden, prevent the problem that other effective requests cannot be received in time, and ensure the local processing capability.

Wherein controlling the BSC to retransmit the request for the MS to be handed over from the source cell to the target cell specifically comprises:

triggering the BSC to resend the request for switching the MS from the source cell to the target cell by sending an assignment request to the BSC; or,

the BSC resends the MS request to handover from the source cell to the target cell by releasing the MS's call.

If the MS is allowed to initiate handover, S305-S311 are performed.

S305, the BSC sends a wireless handover command to the MS, and informs the MS to perform handover.

S306, the MS accesses the target cell and sends a wireless switching detection message to the BSC.

S307, BSC sends MSC SERVER a switch detect message to inform MSC SERVE that MS has accessed the target cell.

S308, the MS sends a wireless switching completion message to the BSC.

S309, the BSC sends a handover complete message to MSC SERVER, informing MSC SERVER that the handover has been completed.

S310, continue the call setup process.

S311, the call establishment is completed, and the call enters a steady state.

In the application example provided by the invention, when the BSC performs the directional retry, compared with the prior art, the interaction with the BSC where the target cell is located is reduced by acquiring the information managed by the same BSC of the source cell and the target cell, so that the signaling interaction is reduced, and the switching speed is improved. In general, timing retry is applied to a situation where an access cell is congested during call setup, and a call can be transferred to other cells that are relatively idle through directional retry. After the invention is adopted, because of the simplification of the processing and the reduction of the switching time delay, the directional retry can be applied to the scene of the cell congestion and can also be used for the optimization of the wireless resources. Through directional retry, the wireless resources can be reasonably allocated in the call establishment phase, and the throughput capacity of the system is improved.

In the prior art, a cross-BSC handover procedure is adopted for directional retry, and the traditional handover procedure is complex in processing and relatively large in handover delay, so that the method is not suitable for being applied to a frequently-occurring scenario, and is generally applied to a scenario of changing a call access cell when the infrequent cell is congested.

By adopting the method of the invention, because the signaling overhead and the switching time delay of the external switching process are reduced, the directional retry speed can be obviously improved, thus the directional retry not only can be applied to the scene of cell congestion, but also can be used for the purpose of optimizing the wireless resources of the cell. When the cell wireless resource is optimized, the utilization rate of the cell wireless resource can be improved through frequent directional retries.

In summary, the method of the present invention can effectively increase the directional retry speed, and can expand the range of the directional retry application due to the increase of the directional retry speed.

Fig. 4 is a schematic structural diagram of an embodiment of a handover management apparatus according to the present invention. In conjunction with the methods illustrated in fig. 2 and 3, the embodiment of the apparatus illustrated in fig. 4 includes:

an obtaining module 401, configured to obtain directional retry information that a Mobile Station (MS) needs to be handed over from a source cell to a target cell, where the directional retry information includes information that the source cell and the target cell are managed by a same Base Station Controller (BSC);

a management module 402, configured to directly make a handover response to a Base Station Controller (BSC) managing the source cell.

Fig. 5 is a schematic structural diagram of the obtaining module 401 in the embodiment of the apparatus shown in fig. 4. The acquisition module 401 shown in fig. 5 includes:

a sending unit 501, configured to send an assignment request to the BSC;

a first receiving unit 502, connected to the sending unit 501, configured to receive, from the BSC, a request for handover of the MS from the source cell to the target cell, where the request includes information that a handover reason is directional retry;

a first determining unit 503, connected to the first receiving unit 502, configured to directly determine, from the request including the handover reason, that the MS needs to be handed over from the source cell to the target cell under a directional retry condition.

Wherein the request including the handover reason received by the first receiving unit 502 is sent by the BSC after determining that the target cell is managed locally.

The obtaining module 401 is configured to determine that the source cell and the target cell are managed by the same BSC according to that a message format of a request for the MS to switch from the source cell to the target cell is the same as a message format of an external handover request.

Fig. 6 is a schematic structural diagram of the management module 402 in the embodiment of the apparatus shown in fig. 4. The management module 402 shown in FIG. 6 includes:

a first judging unit 801, configured to judge whether the handover requested by the BSC can be supported locally;

a notifying unit 802, configured to notify the BSC that the codec used for the call with the directional retry is changed from full rate to half rate when the BSC can locally support the handover requested by the BSC.

Fig. 7 is another structural diagram of the management module 402 in the embodiment of the apparatus shown in fig. 4. The management module 402 shown in FIG. 9 includes:

a second determining unit 701, configured to determine whether the local area can support the handover requested by the BSC;

a control unit 702, configured to control the BSC to resend the request for the MS to switch from the source cell to the target cell when the BSC-requested handover cannot be supported locally.

Wherein the control unit 702 is configured to:

Wherein the apparatus may be provided as a network element alone or integrated on an existing network element (e.g., MSCSERVER).

Compared with the prior art, the device embodiment provided by the invention has the advantages that when the BSC performs the directional retry, the interaction with the BSC where the target cell is located is reduced by acquiring the information managed by the same BSC of the source cell and the target cell, so that the signaling interaction is reduced, and the switching speed is improved. In general, timing retry is applied to a situation where an access cell is congested during call setup, and a call can be transferred to other cells that are relatively idle through directional retry. After the invention is adopted, because of the simplification of the processing and the reduction of the switching time delay, the directional retry can be applied to the scene of the cell congestion and can also be used for the optimization of the wireless resources. Through directional retry, the wireless resources can be reasonably allocated in the call establishment phase, and the throughput capacity of the system is improved.

It will be understood by those of ordinary skill in the art that all or part of the steps of the above embodiments may be implemented using a computer program flow, which may be stored in a computer readable storage medium and executed on a corresponding hardware platform (e.g., system, apparatus, device, etc.), and when executed, includes one or a combination of the steps of the method embodiments.

Alternatively, all or part of the steps of the above embodiments may be implemented by using an integrated circuit, and the steps may be respectively manufactured as an integrated circuit module, or a plurality of the blocks or steps may be manufactured as a single integrated circuit module. Thus, the present invention is not limited to any specific combination of hardware and software.

The devices/functional modules/functional units in the above embodiments may be implemented by general-purpose computing devices, and they may be centralized on a single computing device or distributed on a network formed by a plurality of computing devices.

Each device/function module/function unit in the above embodiments may be implemented in the form of a software function module and may be stored in a computer-readable storage medium when being sold or used as a separate product. The computer readable storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, etc.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A method for handover management, comprising:

acquiring directional retry information of a mobile terminal MS needing to be switched from a source cell to a target cell, wherein the directional retry information comprises information that the source cell and the target cell are managed by the same base station controller BSC;

directly making a handover response to the BSC managing the source cell:

the directly responding to the handover to the base station controller BSC managing the source cell includes:

judging whether the local can support the switching requested by the BSC; when the local can support the switching requested by the BSC, informing the BSC to change the codec used by the call with the directional retry from full rate to half rate; and when the local can not support the handover requested by the BSC, controlling the BSC to retransmit the request of the MS for switching from the source cell to the target cell.

2. The method of claim 1, wherein obtaining the directional retry information that the MS needs to be handed over from the source cell to the target cell comprises:

sending an assignment request to the BSC;

3. The method of claim 2, wherein the request including the cause of the handover is sent by the BSC after determining that the target cell is managed locally.

4. A method according to any of claims 1 to 3, characterized in that the information that the source cell and the target cell are managed by the same base station controller BSC is obtained by:

5. The method of claim 1, wherein controlling the BSC to retransmit the request for the MS to handover from a source cell to a target cell comprises:

6. A handover management apparatus, comprising:

an obtaining module, configured to obtain, in a call setup process, information that a mobile station MS needs to be handed over from a source cell to a target cell under a directional retry condition, where the directional retry information includes information that the source cell and the target cell are managed by a same base station controller BSC;

a management module, configured to directly make a handover response to the BSC managing the source cell:

the management module comprises: a first judging unit and a notifying unit, wherein,

a first judging unit, configured to judge whether the local area can support the handover requested by the BSC; a notifying unit, configured to notify the BSC that the codec used for the call with the directional retry is changed from full rate to half rate when the BSC can locally support the handover requested by the BSC; or,

the management module comprises: a second judgment unit and a control unit, wherein,

a second judging unit, configured to judge whether the local area can support the handover requested by the BSC; and the control unit is used for controlling the BSC to resend the request of the MS for switching from the source cell to the target cell when the local can not support the switching requested by the BSC.

7. The apparatus of claim 6, wherein the obtaining module comprises:

a sending unit, configured to send an assignment request to the BSC;

8. The apparatus of claim 7, wherein the request including the reason for handover received by the first receiving unit is sent by the BSC after determining that the target cell is managed locally.

9. The apparatus according to any of claims 6 to 8, wherein the obtaining module is configured to determine that the source cell and the target cell are managed by the same BSC according to that a message format of a request for handover of the MS from the source cell to the target cell is the same as a message format of an external handover request.

10. The apparatus of claim 6, wherein the control unit is configured to: